Direct volume manipulation for visualizing intraoperative liver resection process

Abstract

This paper introduces a new design and application for direct volume manipulation for visualizing the intraoperative liver resection process. So far, interactive volume deformation and resection have been independently handled due to the difficulty of representing elastic behavior of volumetric objects. Our framework models global shape editing and discontinuous local deformation by merging proxy geometry encoding and displacement mapping. A local-frame-based elastic model is presented to allow stable editing of the liver shape including bending and twisting while preserving the volume. Several tests using clinical CT data have confirmed the developed software and interface can represent the intraoperative state of liver and produce local views of reference vascular structures, which provides a "road map of vessels" that are key features when approaching occluded tumors during surgery.

Surface deformation analysis of collapsed lungs using model-based shape matching

“…To investigate this issue, [8] and [10] studied compensation mechanisms in laparoscopic surgery. Integrating biomechanical models [14, 15] with the proposed statistical models could be a solution to improve clinical applicability. As future work, we are considering a clinical application of the statistical models for VATS to CBCT data acquisition.…”

Estimation of External Forces on the Basis of Local Displacement Observations of an Elastic Body

“…We regard local displacement as a known quantity because deformation measurement methods are often available, such as measurement of surface deformation of elastic bodies using camera images [2][3][4][5] and measurement of inner deformation using ultrasonography [6]. In this study, we assume that the known quantity u o includes the displacement of inner vertices.…”

“…This presents a possibility of error or medical malpractice including injury to organs or unexpected rupture of blood vessels from excess force. To remedy this, various intraoperative measurements and physical estimations of the deformed organs [2][3][4][5][6][7] have been attempted. Soft tissues, including organs, are deformed during surgery because of tensile forces exerted by the forceps, the progress of surgery, the state of pneumoperitoneum, and the breath of the patient.…”

“…Soft tissues, including organs, are deformed during surgery because of tensile forces exerted by the forceps, the progress of surgery, the state of pneumoperitoneum, and the breath of the patient. Image processing studies such as feature point extraction methods using 3D endoscopes [2][3][4][5] have been attempted to measure the deformation of organs. In addition, ultrasonography is usually used for specifying the location of tumors and is helpful in measuring deformation [6].…”

Augmented-reality visualization for improved patient positioning workflow during MR-HIFU therapy

“…They are used in numerous medical applications to provide patient tracking and an augmented visualization through image fusion. 7,8 Wang et al 9 performed MR image fusion on CT scans by automatically detecting and tracking markers located on the patient skin, achieving a patient-to-image registration. Similarly, in Lai et al 10,11 CT images were overlaid on top of the endoscopic view, by using an optical tracking system for endoscope tracking to conduct experiments on a phantom model, reaching a good accuracy in tracking and rendering the augmented view.…”